In the field of dot matrix printing, particularly in the field of non-impact dot matrix printing, a control system must be used whereby data containing information relative to text to be printed is converted to produce preselected characters or patterns. These characters or patterns will be produced as a result of data contained in memory banks which store dot patterns of various fonts. Such fonts must first be placed in storage in the printer memory, for example by burning into memory units such as PROMS.
Various schemes have been used in the past to write fonts into the memory of a control unit or computer. These prior schemes of producing fonts were usually slow and time consuming. The basic method of creating fonts consisted basically of an artist, or draftsman, creating on a page of graph paper a large rendition, one to two feet high, of the character to be digitized. This individual would then manually select what he considered to be the best distribution of the dots. The dot pattern would then be manually entered into a computer memory by typing one key per dot.
Such methods suffered because of two problems: first, the method was too slow, about half a day per character and second, the letters were inconsistent throughout the font design. As the artist or draftsman worked, he would unconsciously change his rules for designing the fonts This would result in an uneven appearance of the font sets.
Font creating modules have been developed for automatically creating fonts for dot matrix printers. Although such modules have increased the speed with which fonts can be stored, they lack the ability to simulate the type of print for which the fonts are to be used. For example, laser and light emitting diode printers produce dots with a Gaussian shape, thermal printers produce a rectangular dot with curved corners, hereinafter referred to as curvalinear rectangle, and a pin dot matrix printer, which is an impact printer, produces a disc shaped dot. Prior font creating modules are unable to tailor such dot shapes.